Improvement in redttcing-g-ear for steam-engine indicators



itd States HENRY L. RRnvOORr, or BROOKLYN, NEW YORK.

Leners Patent No. 100,592, dated Mmh s, 1870.

IIIMPRV'EIMIEN'I.` IN `REDUCING--G-IEEAR FOR STEAM-NG-INE INDICATORS.

. The Schedule referred to in these Letters ?a.tent and making part ofthe same.

To all whom. t may concern Be it known that-I, HENRY L. BRnvooRr, ofBrook lyn, in the county of Kings, and State of New York, have inventeda new andimproved Reducing-Gear for Steam-Engine Indicators; and I dohereby declare that the following is a full, clear, and exact descrip'-tion, reference being had to the accompanying drawlng.

In the application of `the steamengine indicator, the want ofsomeconveuieut and universally applicable means of transmitting motionfrom the pistou of the engine to the card-barrel ot' the indicator hasbeen very much felt. It has been customary to rig up temporalily, tosuit each particular case, a lever which, by means of connecting cords,would produce a suitably reduced movement of the card-barrel, and which,after it has been used, has been thrown aside.

This invention consists in a portable reducing-gear of novelconstruction, provided with pulleys, and which can be convenientlychanged to suit engines ot' dierent'strokes of pistou.

To enable others skilled in the art to make and use my invent-ion, Iwill proceed to describe it, with reference to the accompanyingdrawings, in which- Figure l is a front view'ot' my improved reducinggear. g

Figure2 is a central section ot' the same, perpendicularto iig. `1.

Figure 3 is a back viewof the same with its back cover removed.

Similar letters of reference indicate corresponding parts in theseverakgures.

A is a plate or open box, having arranged across and parallel with itsface, and iirmly secured to it by screws a a or otherwise a bar, B. Thisplate oi' box and bar constitute the fra-min g or case ofthe apparatus.

C and D are two spindles fitted to turn freely in bearings in the plateA and bar B, the spindle C having firmly secured to it, between the saidplate and` bar, a spur-gear, E, and the spindle D having firmly lsecured to it, between the said plate and bar, a much smaller spur-gearor punou, F, gearing with E.

Attachedto the rear end ofthe spindle C `is a spring, G, which is coiledup within and attached to the inside of a box, H, provided ou the backofthe plate A.

This box is provided with a lid or cover, I, which is omitted in tig. 3,to expose the spring to view. The turning of the gear E in one directionproduces such a tension on the spring G as will vcause it to turn backthe said gear in the opposite direction, when the latter is liberated.

The spindles Gand D protrude smedistance through the bar B, and theparts so protruding are made of taper form or otherwise, so formed as toprovide for the ready attachment to or detachment from them of `twoflanged pulleys J' and K. Several suchv pulleys of different sizes areprovided, which may be readily changed on each spindle at pleasure; andto facilitate vthe changing of thel pulleys and allow a greater numberof' changes to `be made with a given'number of pulleys, the two spindlesC and D should have those portions which receive the pulleys made ofuniform size, that either pulley may be placed on either spindle.

To apply the reducing-gear to make this connection between thesteam-engine piston and the card-barrel of the indicator, for thepurpose of transmitting motion to the latter from the former, the plateA is attached to any convenient iixed support, permanent or temporary,by screws or otherwise, in such `position that a cord attached to andwound upon the pulley K may be attached to the pistou-rod of the engine,and that a cord wound upon the pulleyJ may be attached to the pulley onthe card-barrel of the indicator. The movement of the engine pistonthen, by means of the cord attached to and wound on the pulley7 K, turnsthe said pulley and its spindle D and pinion F, and the said pinioncommunicates rotary motion to the gear E and its spindle O and pulley J,and the cord attached to the latter pulley turns the card-barrel oftheiudicator.` i

In this operation the greater circumferenceV of the gear E, as comparedwith that of the pinion F, causes the movement of the cord connectingthe pulley J with the pulley ou the card-barrel to be much reduced, ascompared with the movement of the cord connecting the pulley K with thelpiston-rod, and hence, with a proper relation betweenV the sizes ofthetwo pulleys J and K, a piston of long stroke will not produce more thanasutiicient portion of a single revolution of the card cylinder toenable the card 7 to be obtained.

The relative circumferences of the pinion F and gear E, and the lengthot stroke of the engine piston, and

circumference of the card-barrel. being known, it will' be a mattei' ofeasy calculation for the engineer to apply to the spindles G and DpulleysJ and K, of proper relative sizes t'o obtain from the piston ofthe engine a proper movement of the card-barrel to obtain cards of therequisite length.

What I claim as my invention, and desire to secure by LettersPatei1t,is-

A reducing gear for steam-.engine indicators, cousisting of a gear-,.E,and pinion, F, spindles C and D, and pulleys J and Kthe whole arrangedand applied in a suitable framing or case, to operate substantially asherein described.

HENRY L. BREVOORT.

Witnesses:

FRED. HAYNES, HENRY PALMER.

